1. Field of the Invention
The present invention is directed generally to a combustion heater, and more specifically, to a combustion heater that includes a liquid fuel tank and that can be stored in a substantially-vertical orientation with minimal or no leakage of liquid fuel from the liquid fuel tank.
2. Description of Related Art
Traditional heaters, such as kerosene, direct-fired forced air heaters, typically include a combustion chamber coupled to a fuel tank and a fall for pushing ambient air through the heater. Once the air has been heated, the fall forces the air from the heater into the room being heated. To make larger models mobile, the heater can also be equipped with a set of wheels allowing an operator to transport the heater in manner analogous to that in which a commercial dolly is maneuvered. The fuel tank is typically a large, elongated horizontal cavity in which a liquid fuel such as kerosene is stored prior to being consumed by the heater. The liquid fuel is metered into the combustion chamber of the heater where it is exposed to an ignition source, thereby causing combustion of the fuel.
Conventional heaters typically include a hose that runs from an inlet formed in the fuel tank to a nozzle through which the fuel is injected into the combustion chamber. When the heater is tilted in slightly fi-om its horizontal position in which the heater is fired, such as when the heater is being relocated from one location to another, liquid fuel in the fuel tank either sloshes into the hose towards the nozzle, or is forced by gravity into the hose toward the nozzle. Either way, liquid fuel leaks through the nozzle and out of the heater. The amount of the leakage is worsened when the fuel tank is full. Any leakage of liquid fuel from the fuel tank results in a hazardous condition that can expose nearby people to toxic fumes as well as lead to accidental fires.
Additionally, direct-fired forced air heaters are typically formed as cylindrical combustion chambers. Ambient air is drawn into the combustion chamber at one end, heated within the chamber when exposed to the combusting fuel, and forced fi-om the other end of the combustion chamber as heated air. The end into which the ambient air is drawn is open, thereby exposing this end to the ambient environment. Pollutants and other foreign objects entering this end of the heater can affect combustion and the overall performance of the heater. Such pollutants and other foreign objects can also shorten the useful of the life of the heater.
Conventional forced air heaters are also designed to be stable while oriented in a generally horizontal orientation in which they are intended to be fired. Such a configuration makes the conventional heaters unstable while oriented in any other orientation. However, due to the significant leakage of fuel from the fuel tank while the heater is oriented other than its horizontal orientation in which it is intended to be fired, there has not before been a need to make the heaters stable in any other orientation. Furthermore, heaters that are equipped with wheels allowing the heater to be relocated from one position to another expose the wheels to the ambient environment being heated. Such a configuration makes conventional heaters susceptible to damage, and complex to assemble.
Accordingly, there is a need in the art for a mobile combustion heater that can be readily relocated from one position to another while minimizing or eliminating the leakage of fuel from the fuel tank. The heater can optionally also be stored in orientations other than the orientation in which it is intended to be fired with minimal or no leakage of fuel from the fuel tank while so oriented. The heater can also optionally minimize the amount of debris and pollutants that can enter the combustion chamber through the end of the heater into which ambient air is drawn.